Rail-bond for electric railways.



PATENTED AUG. 11, 1908.

W. E. OAKLEY. RAIL BOND FOR ELECTRIC RAILWAYS.

APPLICATION FILED DEG. 2, 1904.

. 11 W J5 I c 1" L eases Wang??? 5 119 M I E HAW WILLIAM E. OAKLEY, OF MILLBURY, MASSACHUSETTS, ASSIGNOR TO WORCESTER STEEL UNITED STATES PATENT OFFICE.

FOUNDRY COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSA- f CHUSETTS.

RAIL-BOND FOR ELECTRIC RAILWAYS.

Specification of Letters Patent.

Patented Aug. 11, 1908.

Application filed. December 2, 1904. Serial No. 235,196.

To all whom it may concern:

Be it known that I, WILLIAM E. OAKLEY, a citizen of the United States, residing at Millbury, in the county of Worcester and Commonwealth of Massachusetts, have invented a new and useful Improvement in Rail-Bonds for Electric Railways, of which the following is a specification, accompanied by drawings forming a part of the same, in w ich- Figure 1 is a perspective view of the adjoining ends of two rails of an electric railway, connected by a rail bond constructed according to my improved method. Fig. 2

- portion of a founders ask showing one half of the matrix for casting the terminal with one end of the flexible connection placed in gosition to be embedded therein.

imilar reference letters and figures refer to similar parts in the different views.

My invention consists in an improvement upon the method of makingrail bonds described in my application, Serial No. 156,874,

filed May 13,- 1903. In that application I have described a method of making rail bonds in which the metal of the terminal possessed a temperature coefficient similar to that of the metal of the rail, and where the ends of the flexible connection between the terminals were inserted in the matrix of the terminal mold. The molten steel or like metal for the terminal was delivered with a considerable force and at an extremel high temperature upon the ends of the exible connection of copper or like metal with low electrical resistance, from which resulted both a fusion of the copper connection and also a considerable mechanical agitation of the particles of copper and a mixture of them through the metal of the terminal. This formed aterminal which ossessed the good qualities of both meta s without the disadvantages attending'the use of eithermetal alone,

to wit, either increased resistance, if the terminal were made entirel of steel, or a difference in expansion an contraction if the terminal were entirely of copper, which soon destroyed the union of the terminal and the rail and reduced the electrical conductivity of the bond.

The method pointed out in my ending application, Serial No. 156,874, argely decreased the electrical resistance of the terminal because of the intermingled copper, and also, because largely composed of steel, the terminal formed a perfect joint with the rail, which does not deteriorate by expansion or contraction or other influences incident to a terminal made entirely of copper. As the intermingling of the copper and the steel was due entirely to the impact of the molten steel upon the end of the copper cable, it is a matter which can not be accurately determined and an even distribution of the copper through the steel obviously does not occur. In order also to facilitate proper melting and mingling of the connector by the impact of the molten steel, I preferably constructed the connector of a number of small wires twisted together forming a cable instead of one solid wire. The portion of the cable entering the terminal which was not melted formed a less perfectly welded joint than the surface of a solid cable, and the heat necessary to fuse the twisted cable had tended to disintegrate or burn that ortion of the-cable immediately adjacent to he melted portion.

Referring to the accompan ing drawings 1, 1, denote portions of two a jacent rails of an electric railway, 2 is a flexible connection and 3, 3, are the terminals of arail bond uniting the rails 1, l, and constructedaccording to my improved method. The connector 2 may be of any desired construction, in the present instance consisting of a single copper wire. The terminal 3 cast as hereafter described, is provided on one side with a cylindrical extension 4 having its outer surface slightly tapered from a shoulder 5 toward its end. The end of the extenslon 4 is provided mixture.

taper of the surface is referably about one sixtieth ofan inch an the terminal is applied to the rail by forming a round hole 9 m the web 8 of the rail substantially of the same diameter as that of the smaller end of the ex tension 4. The extension 4 is then driven or ressed into the hole 9 forming a tight fit and the rim 7 is u set, thereby expandi the recessed end an holding the termina securely in place. v

By my improved method the terminal 3 is cast in a suitably sha ed matrix 10 conveniently formed in foun ers sand in a flask 11 with a suitable channel 12 for the admission of the molten I metal, the composition of which will hereafter be described. The connector 2, consisting of a cable or preferably a wire of copper or other metal having a similar low electrical resistance, is inserted in the flask with its end 13 projectin into the matrix 10 so as to be surrounded y the molten metal of the terminal 3. The terminal is cast from an alloy of metal consisting of steel or other metal having a temperature coefiicient approximating that of the rail, mixed with copper or other metal which possesses a similar ow degree of resistance to an electric current. This mixture is made before the terminal is cast and the metals composing it can be united in any desired proportion, and care can be exercised to obtain a thorough Of course any metal besides coper, having the necessary quality, to wit, 0w resistance, may be used to form this alloy and I am not restricted to the metal of the flexible connector. After this alloy is formed the terminal is cast at a welding heat around the connector 2 which is thereby united to it, but which retains its shape and position in the center of the terminal. As the end 13 is not to be melted, but sim ly a welded joint is re uired between the sur ace of the connector an the metal of the terminal, a very much smaller degree of heat in the metal of the terminal may be employed so-that the integrity of the co per wire is substantially undisturbed an the deterioratin effect of the excessive heat required to me t the end of the connector is avoided. I am also enabled to use a solid wire connector between the terminals instead of a cable of twisted wires, thereby obtaining a better welding surface and more secure oint between the connector and the terminal than has been heretofore possible. A terminal constructed according to my mproved method has then a center consistmg of a solid wire or cable of copper'or other metal of low resistance welded to a surrounding terminal composed of an alloy of a metal ientl accomplished in a crucible and is whol y under control,-and it may be cast at a temperature but sli htly above the welding heat of the metal 0 the connector. A solid wire may be used for the connector to which the terminal may be firmly welded without any deterioration of the metal of the connector. By this method I am also enabled to alloy the terminal with any desired roportion of. metal of a low resistance, an to secure a more intimate and uniform comminglin change in the temperature coefficlent of the terminal. tivity of a bond prepared'according to my improved method is much increased, while its durability and electrical conductivity under expansion and contraction and other disturbmg causes remains unaffected.

The electrical connection between the terminal and the connector is of course erfect being formed by a weldin joint, an after the terminal is cast about the end of the connector, the bond is, then completed by turning or milling the exterior surface of the-extension.

What I claim as my invention and desire to secure by Letters Patent is 1. A rail bond for electric railways, comprising a connector and a pair of terminals, welded to said connector, and composed of an alloy, formed before said welding, comprising a metal having a temperature coefficient substantially the same as that of the rail, and a metal having a low electrical resistance.

2. A rail bond for electric railways, comprising a connector and a pair of terminals welded to said connector, and composed of an alloy com rising a metal havin a temerature coe cient substantially t e same as that of the rail, and a metal having a low electrical resistance, said metals being mixed to form said alloy in predetermined propor-' tions. 7

3. A rail bond for electric railways, comprising a connector and a pair of terminals, said terminals held in electrical contact with the surface of said connector and composed of an alloy comprising, in predetermined pro ortions, a metal having a temperature coe cient substantially the same as-that of the rail, and a metal having a low electrical resistance.

4. As an article of manufacture, a rail bond for uniting the rails of an electric railway, and consisting of a connector and a air of terminals, said connector having a ow electrical resistance and said terminals being cast and composed of two metals, thoroughly mixed before casting, one of said metals having a normal tem erature coeffi- I find that the electrical conduc' of the metals without material cient approximating that of t e rail, and the other of said metals having a low electrical resistance.

5. A rail bond for electric railways, comhaving a temperature coefficient substanprising a connector and a pair of terminals in tially the same as that of the railand a metal electrical contact, said connector composed having a low electrical resistance. of a metal having a low electrical resistance WILLIAM E. OAKLEY.

5 and said terminals composed of an alloy Witnesses:

formedbeforethe contact of saigl connector PENELOPE CoMBERBAoH, and sald terminals, and comprising a metal RUFUs B. FOWLER 

